Light emitting diodes, components and related methods

ABSTRACT

Light emitting diodes, components, and related methods, with improved performance over existing light emitting diodes. In some embodiments light emitter devices included herein include a submount, a light emitter, a light affecting material, and a wavelength conversion component. Wavelength conversion components provided herein include a transparent substrate having an upper surface and a lower surface, and a phosphor compound disposed on the upper surface or lower surface, wherein the wavelength conversion component is configured to alter a wavelength of a light emitted from a light source when positioned proximate to the light source.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority to co-pending U.S. Provisional PatentApplication Ser. No. 62/366,961, filed on Jul. 26, 2016, the entiredisclosure of which is incorporated by reference herein.

TECHNICAL FIELD

The subject matter disclosed herein relates generally to light emittingdiodes (LEDs), components, and related methods. More particularly, thesubject matter disclosed herein relates to devices, components andmethods to improve emitting performance of LEDs.

BACKGROUND

Light emitting diodes or LED chips are solid state devices that convertelectrical energy into light. LED chips can be utilized in light emitterdevices or components for providing different colors and patterns oflight useful in various lighting and optoelectronic applications. Lightemitter devices can include surface mount devices (SMDs) which can bemounted directly onto the surface of an underlying circuit component orheat sink, such as a printed circuit board (PCB) or metal core printedcircuit board (MCPCB). SMDs can comprise bottom electrical contacts orleads configured to directly mount to the underlying circuit component.SMDs can be used in various LED light bulb and light fixtureapplications and are developing as replacements for incandescent,fluorescent, and metal halide high-intensity discharge (HID) lightingapplications.

Manufacturers of LED lighting products are constantly seeking ways toreduce their cost in order to provide a lower initial cost to customers,and encourage the adoption of LED products. Devices and componentsincorporating fewer raw materials at sustained or increased brightnesslevels are desired. Moreover, LEDs that produce light at optimal outputsand under enhance performance, particularly while using the same or lesspower, are becoming more desirable.

Thus, despite the availability of various light emitter devices andcomponents in the marketplace, a need remains for devices, components,and methods which can be produced quickly, efficiently, at a lower cost,and with improved performance characteristics.

SUMMARY

In accordance with this disclosure, substrate based LEDs, components,and related methods having improved manufacturability and customizationare provided and described herein. Devices, components, and methodsdescribed herein can advantageously exhibit improved processing times,ease of manufacture, and/or lower processing costs. Devices, components,and related methods described herein can be well suited for a variety ofapplications such as personal, industrial, and commercial lightingapplications including, for example, light bulbs and light fixtureproducts and/or applications. In some aspects, devices, components, andrelated methods described herein can comprise improved (e.g., lessexpensive and more efficient) manufacturing processes and/or improvedoptical properties including consistent color targeting and improvedreflection.

Solid state lighting apparatuses, such as LEDs, systems, and relatedmethods are provided. An example apparatus can comprise, for example: asubstrate; a plurality of electrically conductive traces disposed overthe substrate; one or more LEDs each electrically connected to at leasttwo of the electrically conductive traces; a reflective material and/ora phosphor or other color conversion component.

These and other objects of the present disclosure as can become apparentfrom the disclosure herein are achieved, at least in whole or in part,by the subject matter disclosed herein.

BRIEF DESCRIPTION OF DRAWINGS

A full and enabling disclosure of the present subject matter is setforth more particularly in the remainder of the specification, includingreference to the accompanying figures, relating to one or moreembodiments, in which:

FIGS. 1A through 1C are various illustrations of example wavelengthconversion components;

FIGS. 2A through 2E are various illustrations of example LED devices;

FIGS. 3A through 3D are various illustrations of example LED devices;

FIGS. 4A through 4D are various illustrations of example LED devices;

FIG. 5 is a perspective view of an example LED device;

FIGS. 6A through 6E are various illustrations of example LED devices;

FIG. 7 is a plan view illustrating traces of an LED device;

FIGS. 8A and 8B are various illustrations of example LED components; and

FIG. 9 is an illustration of an example LED device.

DETAILED DESCRIPTION

In some aspects, solid state lighting apparatuses and methods describedherein can comprise various solid state light emitter electricalconfigurations, color combinations, and/or circuitry components forproviding solid state lighting apparatuses having improved efficiency,improved color mixing, and/or improved color rendering. Apparatuses andmethods such as those disclosed herein advantageously cost less, aremore efficient, vivid, and/or brighter than some other solutions.

Unless otherwise defined, terms used herein should be construed to havethe same meaning as commonly understood by one of ordinary skill in theart to which this subject matter belongs. It will be further understoodthat terms used herein should be interpreted as having a meaning that isconsistent with the respective meaning in the context of thisspecification and the relevant art, and should not be interpreted in anidealized or overly formal sense unless expressly so defined herein.

Aspects of the subject matter are described herein with reference tosectional, perspective, elevation, and/or plan view illustrations thatare schematic illustrations of idealized aspects of the subject matter.Variations from the shapes of the illustrations as a result, forexample, of manufacturing techniques and/or tolerances, are to beexpected, such that aspects of the subject matter should not beconstrued as limited to particular shapes illustrated herein. Thissubject matter can be embodied in different forms and should not beconstrued as limited to the specific aspects or embodiments set forthherein. In the drawings, the size and relative sizes of layers andregions can be exaggerated for clarity.

Unless the absence of one or more elements is specifically recited, theterms “comprising,” “including,” and “having” as used herein should beinterpreted as open-ended terms that do not preclude the presence of oneor more elements. Like numbers refer to like elements throughout thisdescription.

It will be understood that when an element such as a layer, region, orsubstrate is referred to as being “on” another element, it can bedirectly on the other element or intervening elements can be present.Moreover, relative terms such as “on”, “above”, “upper”, “top”, “lower”,or “bottom” are used herein to describe one structure's or portion'srelationship to another structure or portion as illustrated in thefigures. It will be understood that relative terms such as “on”,“above”, “upper”, “top”, “lower” or “bottom” are intended to encompassdifferent orientations of the apparatus in addition to the orientationdepicted in the figures. For example, if the apparatus in the figures isturned over, structure or portion described as “above” other structuresor portions would now be oriented “below” the other structures orportions.

The terms “electrically activated emitter(s)” and “emitter(s)” as usedherein are synonymous terms and refer to any device capable of producingvisible or near visible (e.g., from infrared to ultraviolet) wavelengthradiation, including for example but not limited to, xenon lamps,mercury lamps, sodium lamps, incandescent lamps, and solid stateemitters, including LEDs or LED chips, organic light emitting diodes(OLEDs), and lasers.

The terms “solid state light emitter(s)”, “solid state emitter(s)”, and“light emitter(s)” are synonymous terms and refer to an LED chip, alaser diode, an organic LED chip, and/or any other semiconductor devicepreferably arranged as a semiconductor chip that comprises one or moresemiconductor layers, which can comprise silicon, silicon carbide,gallium nitride and/or other semiconductor materials, a substrate whichcan comprise sapphire, silicon, silicon carbide and/or othermicroelectronic substrates, and one or more contact layers which cancomprise metal and/or other conductive materials.

The terms “groups”, “segments”, “strings”, and “sets” as used herein aresynonymous terms. As used herein, these terms generally describe howmultiple LED chips are electrically connected, such as in series, inparallel, in mixed series/parallel, in common anode, or in common anodeconfigurations among mutually exclusive groups/segments/sets. Thesegments of LED chips can be configured in a number of different waysand may have circuits of varying functionality associated therewith(e.g. driver circuits, rectifying circuits, current limiting circuits,shunts, bypass circuits, etc.), as discussed, for example, in commonlyassigned and co-pending U.S. patent application Ser. No. 12/566,195,filed on Sept. 24, 2009, U.S. patent application Ser. No. 13/769,273,filed on Feb. 15, 2013, U.S. patent application Ser. No. 13/769,277filed on Feb. 15, 2013, U.S. patent application Ser. No. 13/235,103,filed on Sep. 16, 2011, U.S. patent application Ser. No. 13/235,127,filed on Sep. 16, 2011, and U.S. Pat. No. 8,729,589, which issued on May20, 2014, the disclosure of each of which is hereby incorporated byreference herein in the entirety.

The term “targeted” refers to configurations of LED chip segments thatare configured to provide a pre-defined lighting characteristic that isa specified parameter for the lighting apparatus. For example, thetargeted spectral power distribution can describe the characteristic ofthe light that is generated at a particular power, current, or voltagelevel.

Apparatuses, systems, and methods as disclosed herein can utilize redchips, green chips, and blue chips. In some aspects, chips for use inblue-shifted yellow light (BSY) devices can target different bins as setforth in Table 1 of commonly owned, assigned, and co-pending U.S. patentapplication Ser. No. 12/257,804, published as U.S. Pat. Pub. No.2009/0160363, the disclosure of which is incorporated by referenceherein in the entirety. Apparatuses, systems, and methods herein canutilize, for example, ultraviolet (UV) chips, cyan chips, blue chips,green chips, red chips, amber chips, and/or infrared chips.

The term “substrate” as used herein in connection with lightingapparatuses refers to a mounting member or element on which, in which,or over which, multiple solid state light emitters (e.g., LED chips) canbe arranged, supported, and/or mounted. A substrate can be, e.g., acomponent substrate, a chip substrate (e.g., an LED substrate), or asub-panel substrate. Exemplary substrates useful with lightingapparatuses as described herein can for example comprise printed circuitboards PCBs and/or related components (e.g., including but not limitedto metal core printed circuit boards (MCPCBs), flexible circuit boards,dielectric laminates, ceramic based substrates, and the like, or ceramicboards having FR4 and/or electrical traces arranged on one or multiplesurfaces thereof, high reflectivity ceramics (e.g., alumina) supportpanels, and/or mounting elements of various materials and conformationsarranged to receive, support, and/or conduct electrical power to solidstate emitters. Electrical traces described herein provide electricalpower to the emitters for electrically activating and illuminating theemitters. Electrical traces may be visible and/or covered via areflective covering, such as a solder mask material, Ag, or othersuitable reflector.

In some aspects, a single, unitary substrate can be used to supportmultiple groups of solid state light emitters in addition to at leastsome other circuits and/or circuit elements, such as a power or currentdriving components and/or current switching components. In otheraspects, two or more substrates (e.g., at least a primary substrate andone or more secondary substrate or substrates) can be used to supportmultiple groups of solid state light emitters in addition to at leastsome other circuits and/or circuit elements, such as a power or currentdriving components and/or temperature compensation components. The firstand second (e.g., primary and secondary) substrates can be disposedabove and/or below each other and along different planes, adjacent(e.g., side-by-side) to each other, have one or more co-planar surfacesdisposed adjacent each other, arranged vertically, arrangedhorizontally, and/or arranged in any other orientation with respect toeach other.

Solid state lighting apparatuses according to aspects of the subjectmatter herein can comprise III-V nitride (e.g., gallium nitride) basedLED chips or laser chips fabricated on a silicon, silicon carbide,sapphire, or III-V nitride growth substrate, including (for example)chips manufactured and sold by Cree, Inc. of Durham, N.C. Such LED chipsand/or lasers can be configured to operate such that light emissionoccurs through the substrate in a so-called “flip chip” orientation.Such LED and/or laser chips can also be devoid of growth substrates(e.g., following growth substrate removal). In some cases, LED chips cancomprise red—III-V chips, but not nitride such as InGaAlP, GaAsP, andthe like.

LED chips useable with lighting apparatuses as disclosed herein cancomprise horizontal structures (with both electrical contacts on a sameside of the LED chip) and/or vertical structures (with electricalcontacts on opposite sides of the LED chip). A horizontally structuredchip (with or without the growth substrate), for example, can be flipchip bonded (e.g., using solder) to a carrier substrate or printedcircuit board (PCB), or wire bonded. A vertically structured chip(without or without the growth substrate) can have a first terminalsolder bonded to a carrier substrate, mounting pad, or printed circuitboard (PCB), and have a second terminal wire bonded to the carriersubstrate, electrical element, or PCB.

Electrically activated light emitters, such as solid state emitters, canbe used individually or in groups to emit light to stimulate emissionsof one or more lumiphoric materials (e.g., phosphors, scintillators,lumiphoric inks, quantum dots), and generate light at one or more peakwavelengths, or of at least one desired perceived color (includingcombinations of colors that can be perceived as white). Inclusion oflumiphoric (also called ‘luminescent’) materials in lighting apparatusesas described herein can be accomplished by an application of a directcoating of the material on lumiphor support elements or lumiphor supportsurfaces (e.g., by powder coating, inkjet printing, or the like), addingsuch materials to lenses, and/or by embedding or dispersing suchmaterials within lumiphor support elements or surfaces. Methods forfabricating LED chips having a planarized coating of phosphor integratedtherewith are discussed by way of example in U.S. Patent ApplicationPublication No. 2008/0179611, filed on Sep. 7, 2007, to Chitnis et al.,the disclosure of which is hereby incorporated by reference herein inthe entirety.

Other materials, such as light scattering elements (e.g., particles)and/or index matching materials can be associated with a lumiphoricmaterial-containing element or surface. Apparatuses and methods asdisclosed herein can comprise LED chips of different colors, one or moreof which can be white emitting (e.g., including at least one LED chipwith one or more lumiphoric materials).

In some aspects, one or more short wavelength solid state emitters(e.g., blue and/or cyan LED chips) can be used to stimulate emissionsfrom a mixture of lumiphoric materials, or discrete layers of lumiphoricmaterial, including red, yellow, and green lumiphoric materials. LEDchips of different wavelengths can be present in the same group of solidstate emitters, or can be provided in different groups of solid stateemitters. A wide variety of wavelength conversion materials (e.g.,luminescent materials, also known as lumiphors or lumiphoric media,e.g., as disclosed in U.S. Pat. No. 6,600,175, issued on Jul. 29, 2003,and U.S. Patent Application Publication No. 2009/0184616, filed on Oct.9, 2008, each disclosure of which is hereby incorporated by referenceherein in the entirety, are well-known and available to persons of skillin the art.

In some aspects, lighting apparatuses and systems as described hereincomprise multiple sets of solid state light emitters targeting differentcolors (e.g., one set targeting a first color and at least a second settargeting a second color that is different than the first color. In someaspects, each set of the multiple sets comprises at least two solidstate light emitters of a same color (e.g., the peak wavelengthscoincide). In some aspects, each set of the multiple sets of solid stateemitters is adapted to emit one or more different color(s) of light. Insome aspects, each set of the multiple sets of solid state emitters isadapted to emit one or more color(s) of light that differ relative toone another (e.g., with each set of solid state emitters emitting atleast one peak wavelength that is not emitted by another set of solidstate emitters). Aspects of targeting and selective activating sets ofsolid state emitters according to the present subject matter may beprovided using the circuitry and/or techniques described in commonlyassigned and co-pending U.S. patent application Ser. No. 14/221,839, thedisclosure of which was previously incorporated hereinabove byreference.

The term “color” in reference to a solid state emitter refers to thecolor and/or wavelength of light that is emitted by the chip uponpassage of electrical current therethrough.

Some embodiments of the present subject matter may use solid stateemitters, emitter packages, fixtures, luminescent materials/elements,power supply elements, control elements, and/or methods such asdescribed in U.S. Pat. Nos. 7,564,180; 7,456,499; 7,213,940; 7,095,056;6,958,497; 6,853,010; 6,791,119; 6,600,175, 6,201,262; 6,187,606;6,120,600; 5,912,477; 5,739,554; 5,631,190; 5,604,135; 5,523,589;5,416,342; 5,393,993; 5,359,345; 5,338,944; 5,210,051; 5,027,168;5,027,168; 4,966,862, and/or 4,918,497, and U.S. Patent ApplicationPublication Nos. 2009/0184616; 2009/0080185; 2009/0050908; 2009/0050907;2008/0308825; 2008/0198112; 2008/0179611, 2008/0173884, 2008/0121921;2008/0012036; 2007/0253209; 2007/0223219; 2007/0170447; 2007/0158668;2007/0139923, and/or 2006/0221272; U.S. patent application Ser. No.11/556,440, filed on Dec. 4, 2006; with the disclosures of the foregoingpatents, published patent applications, and patent application serialnumbers being hereby incorporated by reference as if set forth fullyherein.

The terms “lighting apparatus” and “module” as used herein aresynonymous, and are not limited, except that it is capable of emittinglight. That is, a lighting apparatus can be a device or apparatus thatilluminates an area or volume, e.g., a structure, a swimming pool orspa, a room, a warehouse, an indicator, a road, a parking lot, avehicle, signage, e.g., road signs, a billboard, a ship, a toy, amirror, a vessel, an electronic device, a boat, an aircraft, a stadium,a computer, a remote audio device, a remote video device, a cell phone,a tree, a window, an LCD display, a cave, a tunnel, a yard, a lamppost,or a device or array of devices that illuminate an enclosure, or adevice that is used for edge or back-lighting (e.g., backlight poster,signage, LCD displays), light bulbs, bulb replacements (e.g., forreplacing AC incandescent lights, low voltage lights, fluorescentlights, etc.), outdoor lighting, security lighting, exterior residentiallighting (wall mounts, post/column mounts), ceiling fixtures/wallsconces, under cabinet lighting, lamps (floor and/or table and/or desk),landscape lighting, track lighting, task lighting, specialty lighting,rope lights, ceiling fan lighting, archival/art display lighting, highvibration/impact lighting-work lights, etc., mirrors/vanity lighting,spotlighting, high-bay lighting, low-bay lighting, or any other lightemitting device.

In some embodiments the LED devices provided herein can comprise one ormore wavelength conversion components, wavelength conversion materials,color conversion components and/or light converting elements. Suchwavelength conversion components can comprise any suitable lumiphoric orphosphoric material, such as phosphors P, configured to emit a desiredwavelength or light color, such as for example yellow, green, blue, red,and/or white, upon activation or impingement with light emitted by oneor more LED chips of solid state light emitters. A wide variety ofwavelength conversion materials or luminescent materials, also known aslumiphors or lumiphoric media, are disclosed in U.S. Pat. No. 6,600,175,issued on Jul. 29, 2003, and U.S. Patent Application Publication No.2009/0184616, filed on Oct. 9, 2008, each disclosure of which is herebyincorporated by reference herein in the entirety.

Phosphor and phosphor compounds as disclosed herein can comprise one ormore of a wide variety of wavelength conversion materials or colorconversion components including luminescent materials. Examples ofluminescent materials (lumiphors) include phosphors, Cerium-dopedYttrium Aluminum Garnet (YAG), e.g. LuAG:Ce, Nitrides, Oxy-Nitrides,scintillators, day glow tapes, nanophosphors, quantum dots (e.g., suchas provided by NNCrystal US Corp. (Fayetteville, Arkansas), and inksthat glow in the visible spectrum upon illumination with (e.g.,ultraviolet) light. Inclusion of lumiphors in wavelength conversioncomponents, or related components as disclosed herein, in conjunctionwith solid state light emitters and LEDs can be accomplished byproviding layers (e.g., coatings) of such materials over solid stateemitters and/or by dispersing luminescent materials to a clearencapsulant (e.g., epoxy-based or silicone-based curable resin or otherpolymeric matrix) arranged to cover one or more solid state lightemitters. One or more luminescent materials useable in devices asdescribed herein may be down-converting or up-converting, or can includea combination of both types.

Wavelength conversion materials, including those incorporated intowavelength conversion components as disclosed herein, can providebenefits including, for example, improved long term reliability (e.g.,improved properties at around 1000 hours or more and 85° C., 105° C.,and/or 125° C.), decreased bubbling around solid state light emitters, alarger viewing angle, lower dCCT color spread, cooler phosphortemperatures, brighter light emission, improved sulfur resistance,and/or a smaller color point spread, including all or any combination ofsuch features.

As described herein, one or more LED chips can be at least partiallycovered with a wavelength conversion component comprising one or morephosphors and/or one or more layers of phosphors on a clear substrate,such as for example sapphire. In some embodiments such wavelengthconversion components can be referred to as a phosphor-sapphire hat, orPhos hat. Phosphors can be adapted to emit blue light, yellow light,green light, red light, or any combination(s) thereof upon beingimpinged with light emitted via one or more LED chips. That is, in someaspects one or more phosphors in the Phos hat can absorb a portion oflight emitted by the LED chip and in-turn reemit the absorbed light at adifferent wavelength such that the light emitter device or componentemits a combination of light from each of the LED chip(s) and thephosphor(s). In one embodiment, the light emitter devices and componentsdescribed herein can emit what is perceived as white light resultingfrom a combination of light emission from the LED chip and the Phos hat.In one embodiment according to the present subject matter, whiteemitting devices and components can consist of an LED chip that emitslight in the blue wavelength spectrum and a phosphor in the Phos hatthat absorbs some of the blue light and re-emits light in the green,yellow, and/or red wavelength spectrum. The devices and components cantherefore emit a white light combination across the visible spectrum oflight. In other embodiments, the LED chips with a wavelength conversioncomponent, e.g. a Phos hat, can emit a non-white light combination ofblue and yellow light as described in U.S. Pat. No. 7,213,940. LED chipsemitting red light or LED chips covered by a phosphor of a Phos hat thatabsorbs LED light and emits a red light is also contemplated herein.

Wavelength conversion components or Phos hats used in some embodimentswith the disclosed LED components and devices can be made or assembledin any suitable manner. In some embodiments, such wavelength conversioncomponents are produced by applying phosphor only on one surface of thePhos hat so that in assembly of an LED device or component the lightaffecting material (i.e., heavy scatterer to turn light) is rightagainst or substantially adjacent to the Sapphire or Phos hat substrate,giving a clean edge for meniscus control.

In some embodiments, such wavelength conversion components are producedby spraying a substrate, e.g. LED chip, singulated on tape or otherrelease material in a slightly spaced manner, which can allow for somephosphor to be applied on the sidewall of the substrate to form a Phoshat. This approach can in some aspects be useful where white-TiO₂ lightaffecting material is not used or is applied prior to placing of thePhos hat, which can in some embodiments avoid blue light escaping fromsides of a Phos hat.

In some embodiments, substrate wafers can be sprayed, either above roomtemperature, i.e. hot, or at room temperature, to make the Phos hats. Insome aspects it is suitable to spray the wafer at room temperature,followed by curing and then singulating of the die on the wafer.

Other benefits of wavelength conversion materials (e.g., phosphor, P)used in wavelength conversion components as disclosed herein, include,for example, improved far field images (e.g., thereby promoting a veryuniform color appearance in the far field with a larger viewing angle),lower color shifts (lower dCCT), improved long term reliability (e.g.,improved brightness maintenance (optics) at approximately 1000 hours ormore), higher product ratings, cooler phosphor operating temperatures,and/or a lower color point spread, including all or any combination ofsuch features.

Phosphors are one known class of luminescent materials. A phosphor mayrefer to any material that absorbs light at one wavelength and re-emitslight at a different wavelength in the visible spectrum, regardless ofthe delay between absorption and re-emission and regardless of thewavelengths involved. Accordingly, the term “phosphor” may be usedherein to refer to materials that are sometimes called fluorescentand/or phosphorescent. In general, phosphors may absorb light havingfirst wavelengths and re-emit light having second wavelengths that aredifferent from the first wavelengths.

Phosphors can in some embodiments be included in an encapsulant used onan LED device. The phosphor can emit radiation in the visible spectrumhaving lower energy than the radiation emitted by a light emitter anddoes so in response to the wavelength emitted by the emitter.Combinations of phosphors can be used in conjunction with the blue orUV-emitting chip/LED to create white light; e.g. blue and yellow, blueand green and red, and blue and green and yellow and red. Using three ormore colors can provide an opportunity to select a particular whitepoint and a better color rendering. It is also expected that LEDs withmore than one emission peak will be useful in exciting one or morephosphors to produce white light.

Phosphors and/or phosphor compounds can be selectively added and/orapplied in any desired amount or quantity to clear or substantiallyclear substrates, wafers or sheets of material. Application of thephosphor and/or phosphor compounds can be achieved via any suitablemethod including, for example, spraying, gravity sedimentation,centrifugation, addition of a solvent, screen printing, evaporation(sputter, e-beam, thermal, CVD, electrostatic and/or electrophoreticdeposition), dipping, spin coating, direct dispensing, and/or vibration,including for example as described in U.S. Pat. No. 8,410,679 toIbbetson et al., and U.S. Pat. No. 8,425,271 to Hussell et al., thedisclosures of which are each hereby incorporated by reference herein intheir entireties. In some embodiments the phosphor compound applied to aclear substrate, e.g. sapphire wafer, is conformal to the shape and/orsurface of the clear substrate. That is, a conformal layer of phosphoror phosphor compound can, for example, have an at least substantiallyuniform thickness.

The thickness of phosphor compound and/or phosphor layer on the clearsubstrate can, for example, range between approximately 2 μm andapproximately 100 μm, however, any thickness of phosphor compound on thewavelength conversion component can be provided as desired. Thethickness that is used may be selected to reduce or minimize blue lightconversion in a planar surface, self-absorption and/or scattering, andmay depend on the coating process, the density of the phosphor, othercomponents in the phosphor compound, e.g. silicone, and/or the desiredapplication.

The disclosed wavelength conversion components, for example the Phoshats, can provide advantages over existing color changing elements usedwith solid state LEDs. For example, in some embodiments the presentlydisclosed subject matter, and particularly the Phos hats solve orsignificantly improve the problem of blue light conversion in a planarsurface. In some embodiments, coupling the blue TiO₂ processing, asdiscussed herein, with Phos hats can achieve top emitting performancefrom a bottom emitter die. These advantages are particularly evident ascompared to the disadvantages of phosphor in glass (PiGs) and ceramicphosphor plate (CPP), which are widely used but are expensive to make.

More particularly, PiGs are phosphor particles mixed with glass frit,pressed into wafer shapes, fired/sintered in high temperature ovens tobecome PiG-wafers that are then cut to size. CPP is a single crystal YAGphosphor boule that is grown and that is then wafered and sawn intodesired size. As disclosed herein, Phos hats utilize much simpler morereadily available technology to achieve similar or improved results.

As disclosed herein, Phos hats can comprise a sapphire wafer which canbe sprayed with a phosphor compound, such as a phosphor/siliconemixture, to coat phosphor of the desired colorpoint onto a sapphirewafer/hat. Such Phos hats can in some embodiments have significantadvantages, including for example cost, quick turn, very low capital,and sharper corners and flatter surfaces than sintered PiGs. Moreover,there are fewer or no voids or mixing problems as is common with PiGs.Furthermore, there is substantially reduced or no contamination as iscommon with PiGs. Additionally, PiGs have shrinkage during sinteringcausing uneven thicknesses and thus uneven color conversion. Also, PiGsare subject to extreme brittleness so therefore are limited to minimumthicknesses for handling. Conversely, Phos hats can be relatively thin(<80 um) as sapphire wafers are very durable.

As for CPPs, they are inherently expensive to make, such as for examplean order of magnitude more expensive.

Another advantage over existing technology is Phos hats are tunable oradjustable. For example, when spraying, or other appropriate applicationtechnique as discussed herein, phosphor compounds on a pre-singulatedsapphire wafer, this allows the ability to check color within minutes.Post initial spray a Phos hat can be plucked off, tested, and if neededthe remaining PhoS wafer can be quick-sprayed to add more phosphor orphosphor compound as needed to tune in the color point.

The disclosed wavelength conversion components, or Phos hats, cancomprise a glass or other suitable substrate, i.e. a clear orsubstantially clear substrate, for light extraction such as sapphire,acrylic, etc. Phos hats can be made on large substrates, including largesapphire wafers, for example, with larger surface areas as compared toexiting options. Moreover, they can be made uniformly across the widearea, thus they can be matched to die wavelengths to achieve tight colorcontrol on product. Conversely, PiGs and CPPs are made in much smallerwafer sizes. Because in some embodiments a spray application is used,scattering particles and different phosphors can be mixed together toachieve an array of diffusion and color/CRI points. CPP cannot do this.Moreover, PiGs may not be able to do this as the temperatures requiredmay breakdown some components that would work with Phos hats.

In some embodiments all flip chip die can benefit from the disclosedwavelength conversion components by turning a 3D phosphor emission planeinto a 2D emission plane. Additionally, an advantage is that EZ die canbe made into “WZ-like” die with this lower cost method.

Robustness of LED devices can also be greatly enhanced with thedisclosed components given their hard top or solid upper surface versusa silicone top, which is flexible, in traditional LED devices. Suchhard-top or robust LED devices can be useful in applications requiringsuch strength, including for example automotive applications. Moreover,sulfur resistance can in some embodiments be greatly enhanced oversilicone encapsulated components.

Various illustrative features are described below in connection with theaccompanying figures.

FIGS. 1A through 1C are various illustrations of example wavelengthconversion components 100, also referred to as a color conversioncomponents and/or light converting element. In some embodiments,particularly when comprised of phosphor on sapphire, such components canbe referred to herein as Phos hats. FIG. 1A is a side view illustrationof a wavelength conversion components 100 comprising a clear substrate102, or transparent substrate, and a phosphor compound 104 appliedthereto. Phospor compound 104 can be applied to a top T or upper surfaceof clear substrate 102, as illustrated in FIG. 1A, or can be applied toa bottom B or lower surface of clear substrate 102, or in someembodiments on both top T and bottom B. As illustrated in FIG. 1B,wavelength conversion components 100 can comprise a substantially planaror wafer structure comprising a clear substrate 102 with a phosphorcompound 104 applied to a surface thereof, such as for example topsurface T.

Clear substrate 102 can in some embodiments comprise a sapphire wafer,or other suitable clear or transparent material, such as for exampleglass of any kind, acrylic, soda lime, borosilicate, quartz/SiO₂, MgF₂.In some embodiments clear substrate 102 can comprise a rigid or flexibleclear substrate as well as a clear cure silicone sheet, which canprovide the ability to shape a phosphor layer. Phosphor sheets cancomprise phosphor mixed into a silicone matrix and squeegeed flat andfrozen to be used to lay onto a panel populated with die. Such aconfiguration can provide a flexible Phos hat where the substrate cancomprise for example a soft methyl. Such a configuration can in someembodiments be vacuum attached and the soft silicone could conform andseal to a wet attach layer.

In some embodiments the phosphor compound 104 can comprise phosphor,and/or a mixture of phosphor and another material, such as for examplesilicone, silicon (fumed silica), fused silica, TiO₂, and other genericdiffusers. Any scatterer, e.g. fused silica, can be added to the mixturefor packing and homogeneity of emission. TiO₂ in small concentrationscan in some embodiments be used effectively. In some embodiments themixture of phosphor and silicone comprises a ratio of about 1:1 to about6:1, including about 1:1, about 2.5:1, about 3:1, about 4:1, about 4.5:1and/or about 5:1. In some aspects the concentration and/or particle sizeof the phosphor in the phosphor compound is adjustable, wherein theconcentration and/or particle size of the phosphor alters a colorproduced by a wavelength passing through the wavelength conversioncomponent.

Application A of the phosphor and/or phosphor compounds 104 to clearsubstrate 102 can be achieved via any suitable method including, forexample, spraying, gravity sedimentation, centrifuge, addition of asolvent, screen printing, evaporation (sputter, e-beam, thermal, CVD,electrostatic and/or electrophoretic deposition), dipping, spin coating,direct dispensing, and/or vibration, as discussed further herein. Insome aspects, the phosphor compound 104 is substantially uniformlyapplied to the transparent substrate 102 and/or is conformal to thetransparent substrate 102.

Wavelength conversion component 100 as shown in FIGS. 1A through 1C isconfigured to alter a wavelength of a light emitted from a light sourcewhen positioned proximate to the light source, such as for example aLED. Thus, as discussed further herein, component 100 is configured tobe positioned on or proximate to a light source, such as an LED. In someembodiments, and as shown in FIG. 1B, wavelength conversion component100 can comprise any suitable size or configuration as needed forapplication to, on or near a light source such as an LED. For example,width W, length L and height H can be configured as desired, e.g. 40 umto 10 mm long and 5 um to 10 mm wide, or more, to achieve a wavelengthconversion component 100 having an area of about 200 um² to about 5 mm².In some embodiments a wavelength conversion component 100 can be about50 mm² or more. By way of example and not limitation, a wavelengthconversion component can be any desirable size and/or shape, such asabout 30×30 mm, which is an advantage not available in PiGs and CPPs.

As illustrated in FIG. 1A, in some embodiments phosphor compound 104 canbe applied A to substrate 102 and then the wafer can be cut C intodesired dimensions. Alternatively, as illustrated in FIG. 1C, substrate102 can in some embodiments be cut or singulated into clear substrates102S prior to application A of phosphor compound 104. In the approachdepicted in FIG. 1C phosphor compound 104 can in some embodiments beapplied to top surface T as well as along some edges or sides of clearsubstrate 102.

In some embodiments wavelength conversion components, or Phos hats, canbe made by providing a transparent substrate having an upper surface anda lower surface, applying a phosphor compound to the upper surfaceand/or lower surface of the transparent substrate, and curing thetransparent substrate with applied phosphor compound. The resultingwavelength conversion component can in some embodiments be configured toalter a wavelength of a light emitted from a light source whenpositioned proximate to the light source. The transparent substrate cancomprise a sapphire wafer, and the phosphor compound can comprise amixture of phosphor and silicone.

In some embodiments making the disclosed wavelength conversioncomponents, or Phos hats, can further comprise using a stealth laser tocause an internal damage layer in the transparent substrate. In someembodiments using the stealth laser to pitch can occur prior toapplication of the phosphor compound.

Application of the phosphor and/or phosphor compounds to the clear ortransparent substrate can be achieved via any suitable method including,for example, spraying, gravity sedimentation, centrifuge, addition of asolvent, screen printing, evaporation (sputter, e-beam, thermal, CVD,electrostatic and/or electrophoretic deposition), dipping, spin coating,direct dispensing, and/or vibration. The phosphor compound can besubstantially uniformly applied to the transparent substrate such thatit is conformal to the transparent substrate.

In some embodiments, a silicone compound and/or layer can be applied onthe phosphor compound that is applied to the upper surface and/or lowersurface of the transparent substrate.

FIGS. 2A through 2E are various illustrations of example LED devices asprovided herein. In some embodiments FIGS. 2A through 2E can be viewedas steps for making/assembling a LED device as provided herein, althoughvariations in the order of the steps and omission/addition of some stepsis not precluded. FIG. 2A depicts a light emitter device 110 comprisinga submount 112 and one or more light emitters 114 a, 114 b, and 114 cdisposed on submount 112. Any number of light emitters 114 a-c, or LEDs,can be disposed on or applied to submount 112. Additionally, LEDs 114a-c can each have a different targeted color. Although three LEDs areillustrated, device 110 can include a different number of LEDs, e.g.,one or more LEDs.

In some embodiments a submount 112, or substrate, can compriseelectronic traces 116, or conductive traces, but in some examples,device 110 could be based on a leadframe construction where no tracesare on top, or any other appropriate construction. In some embodimentsdie attach material 118, or solder bumps, can be provided to create anelectrical contact between light emitters 114 a-c and electronic traces116.

In some embodiments FIG. 2A depicts a light emitter device 110comprising a submount 112 comprising an upper surface and a bottomsurface and one or more light emitters 114 a-c disposed on the uppersurface of submount 112. In some embodiments the one or more lightemitters 114 a-c each comprise an upper surface, a lower surfaceadjacent to the upper surface of submount 112, and one or more sides.

Turning to FIG. 2B, a light affecting material 120 can be applied todevice 110. In some embodiments light affecting material 120 cancomprise a reflective material, such as for example TiO₂ (also referredto as titania and/or blue TiO₂), A1 ₂O₃, Boron nitride, microcellularpolyethylene terephthalate (McPET) and/or Barium sulfate (spherematerial). In some embodiments light affecting material 120 is appliedto device 110 so at to surround the one or more light emitters 114 a-cdisposed on submount 112. That is, in some embodiments light affectingmaterial 120 can be disposed on the upper surface of submount 112 and/oradjacent to the one or more sides of the one or more light emitters 114a-c. In some embodiments light affecting material 120 is applied at adepth or height substantially similar to a height of light emitters 114a-c such that each side of light emitters 114 a-c are surrounded bylight affecting material 120 on one or more sides of light emitters 114a-c Light emitters 114 a-c can comprise any suitable chip size, shape,and/or thickness. In some aspects, the thickness or height can beapproximately 0.25 mm or more, 0.3 mm or more, 0.4 mm or more, or 0.5 mmor more. By applying the reflective or light affecting material on thesides of the LEDs light emitted from the sides of the LEDs can minimizedthereby focusing the light emission from an upper surface of the LEDs.In some embodiments light affecting material 120 surrounds lightemitters 114 a-c and fills any voids or filets there between, asdepicted in FIG. 2B.

FIG. 2C depicts light emitter device 110 with a clear layer 122 appliedto light emitters 114 a-c. Particularly, in some embodiments a clearlayer 122, in some embodiments comprising a silicone and/or an adhesive,and optionally a scatter compound, can be applied to an upper surface ofone or more of light emitters 114 a-c. Clear or silicone layer 122 canin some embodiments be configured to adhere the wavelength conversioncomponent (see FIG. 2D) to the upper surface of the one or more lightemitters 114 a-c. The scatter compound can comprise fumed silica, fusedsilica, and/or TiO₂. In some aspects, TiO₂ in small percentages can beused for the scattering compound. For example, the percentage of TiO₂can be from around, about or approximately 0.1% to 5.0%. In someaspects, the percentage of TiO₂ can for example be around, about orapproximately 1%. Clear or silicone layer 122 can be applied to the LEDssuch that it substantially or completely covers the upper surfacethereof. In some embodiments the clear layer can be administered suchthat it extends to the edges of the upper surface of the one or moreLEDs on the device, without extending past the edges.

As depicted in FIG. 2D, the wavelength conversion component, or Phoshat, can be applied to device 110 by placing the clear substrate 102with phosphor layer 104 directly above light emitters 114 a-c. Bydisposing wavelength conversion component on the upper surface of theone or more light emitters the Phos hat can affect the light output fromthe LEDs, including improving the uniformity of color produced by device110. In some embodiments, the Phos hat can be applied with the phosphor104 side down as depicted in FIG. 2D. Clear layer 122 can in someembodiments act as an adhesive to adhere substrate 102 with phosphorlayer 104 onto light emitters 114 a-c.

In FIG. 2E a second application of light affecting material 124 can beapplied to device 110. In some embodiments light affecting material 124can comprise a reflective material, such as for example TiO₂ (alsoreferred to as titania and/or blue TiO₂), and can be the same as lightaffecting material 120. In some embodiments light affecting material 124is applied to device 110 so at to surround the Phos hat (substrate 102and phosphor layer 104) on top of LEDs 114 a-c. That is, in someembodiments light affecting material 124 can be disposed on previouslyapplied light affecting material 120 and adjacent to the one or moresides of the Phos hat (substrate 102 and phosphor layer 104) on top ofLEDs 114 a-c. In some embodiments light affecting material 124 isapplied at a depth or height substantially similar to a height the Phoshat such that each side of it is surrounded by light affecting material124. By applying the reflective or light affecting material on the sidesof the Phos hat light emitted from the sides of the LEDs and the Phoshat on top thereof can be minimized thereby focusing the light emissionfrom an upper surface of the LEDs and Phos hat.

In some embodiments device 110, including that depicted in FIG. 2E, canbe cured at an appropriate temperature, such as for example 150° C.

Turning now to FIGS. 3A through 3D, various examples of LED devices asprovided herein are illustrated. In some embodiments FIGS. 3A through 3Dcan be viewed as steps for making/assembling a LED device as providedherein, although variations in the order of the steps andomission/addition of some steps is not precluded. FIG. 3A depicts alight emitter device 110 comprising a submount 112 and one or more lightemitters 114 a, 114 b, and 114 c disposed on submount 112. Any number oflight emitters 114 a-c, or LEDs, can be disposed on or applied tosubmount 112. Additionally, LEDs 114 a-c can each have a differenttargeted color. Although three LEDs are illustrated, device 110 caninclude a different number of LEDs, e.g., one or more LEDs.

In some embodiments a submount 112, or substrate, can compriseelectronic traces 116, or conductive traces, but in some examples,device 110 could be based on a leadframe construction where no tracesare on top, or any other appropriate construction. In some embodimentsdie attach material 118, or solder bumps, can be provided to create anelectrical contact between light emitters 114 a-c and electronic traces116.

In some embodiments FIG. 3A depicts a light emitter device 110comprising a submount 112 comprising an upper surface and a bottomsurface and one or more light emitters 114 a-c disposed on the uppersurface of submount 112. In some embodiments the one or more lightemitters 114 a-c each comprise an upper surface, a lower surfaceadjacent to the upper surface of submount 112, and one or more sides.

FIG. 3B depicts light emitter device 110 with a clear layer 122 appliedto light emitters 114 a-c. Particularly, in some embodiments a clearlayer 122, in some embodiments comprising a silicone and/or an adhesive,and optionally a scatter compound, can be applied to an upper surface ofone or more of light emitters 114 a-c. Clear or silicone layer 122 canin some embodiments be configured to adhere the wavelength conversioncomponent (see FIG. 3C) to the upper surface of the one or more lightemitters 114 a-c. The scatter compound can comprise fumed and/or fusedsilica. Clear or silicone layer 122 can be applied to the LEDs such thatit substantially or completely covers the upper surface thereof. In someembodiments the clear layer can be administered such that it extends tothe edges of the upper surface of the one or more LEDs on the device,without extending past the edges.

As depicted in FIG. 3C, the wavelength conversion component, or Phoshat, can be applied to device 110 by placing the clear substrate 102with phosphor layer 104 directly above light emitters 114 a-c. Bydisposing wavelength conversion component on the upper surface of theone or more light emitters the Phos hat can affect the light output fromthe LEDs, including improving the uniformity of color produced by device110. In some embodiments, the Phos hat can be applied with the phosphor104 side down as depicted in FIG. 3C. Clear layer 122 can in someembodiments act as an adhesive to adhere substrate 102 with phosphorlayer 104 onto light emitters 114 a-c.

Turning to FIG. 3D, a light affecting material 120 can be applied todevice 110. In some embodiments light affecting material 120 cancomprise a reflective material, such as for example TiO₂. In someembodiments light affecting material 120 is applied to device 110 so atto surround the one or more light emitters 114 a-c disposed on submount112, as well as the Phos hat (substrate 102 and phosphor layer 104) ontop of LEDs 114 a-c. That is, in some embodiments light affectingmaterial 120 can be disposed on the upper surface of submount 112 and/oradjacent to the one or more sides of the one or more light emitters 114a-c. In some embodiments light affecting material 120 is applied at adepth or height substantially similar to a height of light emitters 114a-c, including the height of the Phos hat (substrate 102 and phosphorlayer 104) on top of LEDs 114 a-c, such that each side of light emitters114 a-c is surrounded by light affecting material 120. By applying thereflective or light affecting material on the sides of the LEDs lightemitted from the sides of the LEDs can minimized thereby focusing thelight emission from an upper surface of the LEDs and Phos hat.

Turning now to FIGS. 4A through 4D, various examples of LED devices asprovided herein are illustrated. In some embodiments FIGS. 4A through 4Dcan be viewed as steps for making/assembling a LED device as providedherein, although variations in the order of the steps andomission/addition of some steps is not precluded. FIG. 4A depicts alight emitter device 110 comprising a submount 112 and one or more lightemitters 114 a, 114 b, and 114 c disposed on submount 112. Any number oflight emitters 114 a-c, or LEDs, can be disposed on or applied tosubmount 112. Additionally, LEDs 114 a-c can each have a differenttargeted color. Although three LEDs are illustrated, device 110 caninclude a different number of LEDs, e.g., one or more LEDs.

In some embodiments a submount 112, or substrate, can compriseelectronic traces 116, or conductive traces, but in some examples,device 110 could be based on a leadframe construction where no tracesare on top, or any other appropriate construction. In some embodimentsdie attach material 118, or solder bumps, can be provided to create anelectrical contact between light emitters 114 a-c and electronic traces116.

In some embodiments FIG. 4A depicts a light emitter device 110comprising a submount 112 comprising an upper surface and a bottomsurface and one or more light emitters 114 a-c disposed on the uppersurface of submount 112. In some embodiments the one or more lightemitters 114 a-c each comprise an upper surface, a lower surfaceadjacent to the upper surface of submount 112, and one or more sides.

FIG. 4B depicts light emitter device 110 with a clear layer 122 appliedto light emitters 114 a-c. Particularly, in some embodiments a clearlayer 122, in some embodiments comprising a silicone and/or an adhesive,and optionally a scatter compound, can be applied to an upper surface ofone or more of light emitters 114 a-c. Clear or silicone layer 122 canin some embodiments be configured to adhere the wavelength conversioncomponent (see FIG. 4C) to the upper surface of the one or more lightemitters 114 a-c. The scatter compound can comprise fumed and/or fusedsilica. Clear or silicone layer 122 can be applied to the LEDs such thatit substantially or completely covers the upper surface thereof. In someembodiments the clear layer can be administered such that it extends tothe edges of the upper surface of the one or more LEDs on the device,without extending past the edges.

As depicted in FIG. 4C, the wavelength conversion component, or Phoshat, can be applied to device 110 by placing the clear substrate 102with phosphor layer 104 directly above light emitters 114 a-c. Bydisposing wavelength conversion component on the upper surface of theone or more light emitters the Phos hat can affect the light output fromthe LEDs, including improving the uniformity of color produced by device110. In some embodiments, the Phos hat can be applied with the phosphor104 side down as depicted in FIG. 4C. Clear layer 122 can in someembodiments act as an adhesive to adhere substrate 102 with phosphorlayer 104 onto light emitters 114 a-c.

Turning to FIG. 4D, a light affecting material 120 can be applied todevice 110. In some embodiments light affecting material 120 cancomprise a reflective material, such as for example TiO₂. In someembodiments light affecting material 120 is applied to device 110 so atto surround the one or more light emitters 114 a-c disposed on submount112, as well as the Phos hat (substrate 102 and phosphor layer 104) ontop of LEDs 114 a-c. That is, in some embodiments light affectingmaterial 120 can be disposed on the upper surface of submount 112 and/oradjacent to the one or more sides of the one or more light emitters 114a-c. In some embodiments light affecting material 120 is applied at adepth or height substantially similar to a height of light emitters 114a-c, including the height of the Phos hat (substrate 102 and phosphorlayer 104) on top of LEDs 114 a-c, such that each side of light emitters114 a-c is surrounded by light affecting material 120. In order tocontain light affecting material 120 on the upper surface of thesubmount and/or adjacent to the one or more sides of the one or morelight emitters a dam material 130 can be provided/applied by anysuitable technique, e.g. molded, dispensed, etc., around a periphery ofsubmount 112. Dam material 130 can be configured to contain lightaffecting material 120 on the upper surface of submount 112 and/oradjacent to the one or more sides of the one or more light emitters 114a-c whereby the one or more light emitters is surrounded by the lightaffecting material. In some embodiments, and as depicted in FIG. 4D, dammaterial 130 can in some embodiments be configured to extend above theupper surface of submount 112 to a height substantially similar to aheight of the one or more sides of the one or more light emitters 114a-c, such that dam material 130 is configured to contain enough lightaffecting material 120 to surround the one or more light emitters 114a-c at a depth substantially similar to the height of the one or moresides of the one or more light emitters 114 a-c. In some embodiments dammaterial 130 can be more viscous than light affecting material 120. Insome embodiments, an upper surface of the light affecting material 120encapsulating the one or more light emitters 114 a-c is substantiallyplanar to the upper surface of the one or more light emitters. That is,in the configuration depicted in FIG. 4D the light affecting material120 can be applied in such a manner as to create a squared off orsubstantially squared profile with an upper surface substantially planarto the upper surface of the LEDs/Phos hat, with an outer edge that issubstantially vertical. In some embodiments dam material 130 can beremoved after application, and in some embodiments, curing of lightaffecting material 120. By applying the reflective or light affectingmaterial on the sides of the LEDs light emitted from the sides of theLEDs can minimized thereby focusing the light emission from an uppersurface of the LEDs and Phos hat. Such effect can be further enhancedand/or optimized in some embodiments by providing the lightaffecting/reflective material in a squared-off configuration as depictedin FIG. 4D.

In some embodiments dam material 130 can be configured as a high anglelight reflector, such as for when light affecting material 120, or fillmaterial, is clear. Dam material 130 can serve as a reflector of highangle light to make light more useful for application intent, especiallywhen light affecting material 120 is a substantially transparent fillmaterial. In some embodiments molded domes can be coupled with dammaterial 130 for light reflection to increase brightness, i.e. usefullight. Such a configuration can be used with or without a wavelengthconversion component or Phos hat as described herein.

Dam material 130 can in some embodiments comprise a mix of Si₅ with 50%TiO₂, 50% 705F fused silica (roughly phosphor sized glass beads), and 5%A604 fumed silica. In some embodiments dam material 130 can comprise amix of Si₄, OE6370 silicone, 75% TiO₂, 50% fused silica, and 7.5% fumedSilica.

FIG. 5 is a perspective view of an example LED device 140, or LED chip,as disclosed herein. LED device 140 can in some embodiments be the finalproduct of the examples and steps depicted in FIGS. 2A-2E, 3A-3D and/or4A-4D. LED device 140 can in some embodiments comprise a submount 112and one or more light emitters 114 a, 114 b, and 114 c disposed onsubmount 112. Wavelength conversion component 100 (or Phos hatcomprising substrate 102 and phosphor layer 104 as depicted in FIGS. 2D,3C and 4C) can be disposed directly above LEDs 114 a-c. Light emitters114 a, 114 b, and 114 c and wavelength conversion component 100 can besurrounded by light affecting material 120. One or more contacts 128 canbe provided on substrate 112, and in some embodiments can extend underLEDs 114 a-c and/or can be in electrical connection to electronic traces116 (see FIGS. 2A, 3A and/or 4A) to provide electrical connections toLEDs 114 a-c. Contacts 128 can comprise one cathode and one anode. Insome embodiments, LED device 140 can comprise a quick response code QR,or other bar code configured to contain information about the device.

FIGS. 6A and 6B are top plan views of example LED devices 170 and 172,respectively. LED devices 170 and 172 can in some embodiments compriseone light emitter 114 as depicted in FIG. 6A, or one or more lightemitters, such as for example two light emitters 114 a/ 114 b asdepicted in FIG. 6B, or more. A wavelength conversion component, or Phoshat, as disclosed herein can be disposed over the one or more lightemitters. Light emitters 114 or 114 a/ 114 b and the wavelengthconversion component can be surrounded by light affecting material 120.

FIG. 6C depicts a bottom plan view of an example LED device 170/172. Insome embodiments the light emitters, such as light emitters 114 in FIG.6A, can be arranged for mounting using surface mount technology andhaving internal conductive paths, comprising first and second surfacemount pads 176 a and 176 b, respectively, that can be formed on backsurface 174 of submount 112. Conductive vias 178 can be formed throughsubmount 112 such that when a signal is applied to one or both of firstand second surface mount pads 176 a and 176 b it is conducted to one ormore electronic traces on the top surface of submount 112, such aselectronic traces 116 depicted in FIGS. 2A, 3A and/or 4A. In someembodiments, first and second mounting pads 176 a and 176 b can allowfor surface mounting of the LED devices 170/172 with the electricalsignal to be applied to the LED devices 170/172 applied across the firstand second mounting pads 176 a and 176 b.

It is understood that the mounting pads 176 a and 176 b, and vias 178can be arranged in many different ways and can have many differentshapes and sizes. It is also understood that instead of vias, one ormore conductive traces can be provided on the surface of the submountbetween the mounting pads and contact pads, such as along the sidesurface of the submount.

The LED device 170/172 can further comprise a metallized area 180 on theback surface 174 of submount 112, between the first and second mountingpads 176 a and 176 b, respectively. Metallized area 180 is preferablymade of a heat conductive material and is preferably in at least partialvertical alignment the one or more LEDs 114 (FIG. 6A) or 114 a, 114 b(FIG. 6B). In one embodiment, the metallized area 180 is not inelectrical contact with the elements on top surface of the submount 112or the first and second mounting pads 176 a and 176 b on the backsurface 174 of the submount 112. Although heat from the LED is laterallyspread over the top surface of the submount more heat will pass into thesubmount directly below and around the LED. The metallized area canassist with this dissipation by allowing this heat to spread into themetallized area where it can dissipate more readily. It is also notedthat the heat can conduct from the top surface of the submount 112,through the vias 178, where the heat can spread into the first andsecond mounting pads 176 a and 176 b where it can also dissipate. Forthe LED device 170/172 used in surface mounting, the thickness of themetallized area 180 and the first and second pads 176 a and 176 b shouldbe approximately the same such that all three make contact to a lateralsurface such as a PCB.

FIG. 6D is a side view of LED device 170/172, and illustrating anoptical area, including light affecting material 120 near an uppersurface, mounted on submount 112, with one or more copper traces 212 (orother conductive material such as Ni, Pd or Au) thereunder.

FIG. 6E is a top plan view of an example LED device 174. LED device 174can in some embodiments comprise one or more light emitters 114 c and114 d, as depicted in FIG. 6E. A wavelength conversion component, orPhos hat, as disclosed herein can be disposed over the one or more lightemitters. Light emitters 114 c/ 114 d and the wavelength conversioncomponent can be surrounded by light affecting material 120. As shown inFIG. 6E, in some embodiments different phosphor regions, areas or zonescan be disposed over emitters 114 c/ 114 d. Any combinations ofphosphors and colors are possible, including for example a red phosphorregion or zone over emitter 114 c, and a separate yellow and/or greenphosphor region or zone over emitter 114 d. Emitters 114 c/ 114 d, canbe any desired color, such as for example both emitters 114 c/ 114 d cancomprise blue LEDs. The color emitted by the emitter or LED can be colorshifted for example by the phosphor region or zone. U.S. Pat. No.8,998,444, incorporated herein by reference and commonly owned herewith,discloses blue-shifted yellow and/or green plus (+) blue-shifted red.

In some embodiments two or more zones can be helpful where the emissionspectrum of one phosphor overlaps with the activation (or excitation)spectrum of another phosphor. In some embodiments, phosphors andphosphor colors can be layered on each other and on a wavelengthconversion component disposed over an emitter to produced differentcolors and/or color intensities. For example, phosphors can be optimallylayered in one or more layers to achieve a light effect or desiredwavelength. See, e.g., U.S. Patent Application Publication No.2009/0039375, incorporated herein by reference and commonly ownedherewith. For example, a first layer can comprise a red phosphor and asecond layer a yellow phosphor, or vice versa. Additionally, a greenphosphor can be layered on a yellow phosphor that is layered on a redphosphor, for example. Moreover, emitters, such as emitters 114 c/ 114 din FIG. 6E, with different phosphor colors thereon can be separatelycontrollable such that they can be turned on at the same time or atdifferent times.

FIG. 7 is a plan view illustrating a metal trace configuration of anexample LED device 150. In some embodiments the metalized trace depictedin FIG. 6 can comprise a metalized trace corresponding to LED device 140of FIG. 5. LED device 150 can comprise a substrate 126 (in someembodiments similar to substrate 112 of FIG. 5) and one or more contacts128, including one cathode and one anode. Connected to contacts 128 canbe one or more electronic traces 154 and/or contact pads 152, which canbe configured to allow electric current to flow into and out of thesolid state light emitters thereby illuminating the solid state lightemitters. Solid state light emitters can be electrically connected onlyin parallel, only in series, or in an arrangement comprising acombination of parallel and series.

FIGS. 8A and 8B are various illustrations of example LED components 200and 202, respectively. Each of components 200 and 202 can in someembodiments comprise a substrate 210, such as an aluminum nitridesubstrate, and one or more copper traces 212 on substrate 210. A goldinterface 216 can be disposed on and/or above one or more copper traces212. An aluminum pad 220 configured for wire bonding W an LED can bedisposed on a portion of gold interface 216, with a layer of titanium218 between aluminum pad 220 and gold interface 216. The layer oftitanium 218 can be configured to substantially prevent, orsignificantly reduce, galvanic action between aluminum pad 220 and goldinterface 216. A light emitter 114 can be disposed on gold interface216.

In FIG. 8A the layer of titanium 218 and aluminum pad 220 can besubstantially aligned vertically such that titanium 218 is substantiallyand directly below aluminum pad 220. Alternatively, in FIG. 8B aluminumpad 220 can be disposed on top of a layer of titanium 218 that extendspast the edges of aluminum pad 220. As such, titanium 218 is configuredto extend beyond an outer periphery of aluminum pad 220 and provide anadditional insulting effect against galvanic action between the aluminumpad and gold interface. As depicted in the inset of FIG. 8B, showing atop plan view of titanium 218 and aluminum pad 220, titanium 218 isconfigured to extend beyond an outer periphery of aluminum pad 220. Alight emitter 114 can for example be disposed on gold interface 216, anda wire W for wire bonding can for example extend from aluminum pad 220for connecting to other structure.

In some embodiments provided herein are methods of making a LEDcomponent such as those depicted in FIGS. 8A and 8B. Such methods cancomprise providing an aluminum nitride substrate, providing one or morecopper traces on the aluminum nitride substrate, providing a goldinterface on the one or more copper traces, applying a first photo maskto create an opening on the gold interface and applying a layer oftitanium thereon, and applying a second photo mask to create an openingon the layer of titanium and applying an aluminum pad configured forwire bonding the LED. Such a method provides an LED component asdepicted in FIG. 8B having a layer of titanium between the aluminum padand gold interface, wherein the layer of titanium is configured tosubstantially prevent galvanic action between the aluminum pad and goldinterface.

FIG. 9 is an illustration of an example LED device 160. FIG. 9 depictsan LED device, such as that depicted in any of FIGS. 2A-2E, 3A-3D, 4A-4Dand/or 5, enclosed in a lens 162. LED device 160 can comprise a submount112 and one or more light emitters 114 disposed on submount 112. Anynumber of light emitters 114 or LEDs can be disposed on or applied tosubmount 112. In some embodiments a submount 112, or substrate, cancomprise electronic traces 116, or conductive traces, but in someexamples, device 110 could be based on a leadframe construction where notraces are on top, or any other appropriate construction. In someembodiments die attach material 118, or solder bumps, can be provided tocreate an electrical contact between light emitters 114 and electronictraces 116. In some embodiments a clear layer 122, such as silicone, canbe applied to light emitters 114 on top of which a wavelength conversioncomponent (Phos hat), comprising clear substrate 102 with phosphor layer104 directly, can be applied. Finally, as discussed herein, a lightaffecting material 120 can be applied to device 110 so at to surroundthe one or more light emitters 114. A lens 162 can be adhered to orotherwise affixed to substrate 112 and enclose light emitter 114,wavelength conversion component 102/104, and light affecting material120. Lens 162 can provide a protective element to the LED and relatedcomponents, and/or alter light emitted therefrom.

In some examples, LEDs used in the devices and components herein canhave different targeted colors selected so that devices can operate as apixel and produce a range of colors within its color gamut by energizingdifferent combinations of LEDs. For example, LEDs can include UV, blueor green LED chips, such as a group III nitride based LED chipcomprising negatively doped (n-type) epitaxial layer(s) of galliumnitride or its alloys and positively doped (p-type) epitaxial layers ofgallium nitride or its alloys surrounding a light emitting activeregion; a red LED chip, such as an AlInGaP based red LED chip; a whiteLED chip (e.g., blue LED chip with phosphor(s) layer(s)), and/or anon-white phosphor based LED chip.

Traces, electrical contacts, leads and contact pads, as describedherein, can comprise any suitable electrically conductive material,e.g., Cu, finished with electroless Ag, Ni—Ag, ENIG, ENIPIG, HASL, OSP,or the like. Traces can be applied over one or more surfaces of asubstrate via plating (e.g., via electroplating or electroless plating),depositing (e.g., physical, chemical, and/or plasma deposition, CVD,PECVD, etc.), sputtering, or via any other suitable technique. In someaspects, traces can comprise a metal or metal alloy which may contain(in whole or part) copper (Cu), silver (Ag), gold (Au), titanium (Ti),palladium (Pd), aluminum (Al), tin (Sn), combinations thereof, and/orany other suitable conductor.

In some aspects, substrates, such as substrate 112 of FIGS. 2-5, cancomprise a printed circuit board (PCB), a metal core printed circuitboard (MCPCB), a flexible printed circuit board, a dielectric laminate(e.g., FR-4 boards as known in the art), a ceramic based substrate, orany other suitable substrate for mounting LED chips and/or LED packages.In some aspects such substrates can comprise one or more materialsarranged to provide desired electrical isolation and high thermalconductivity. For example, at least a portion of such substrates maycomprise a dielectric to provide the desired electrical isolationbetween electrical traces and/or sets of solid state emitters. In someaspects, such substrates can comprise ceramic such as alumina (Al₂O₃),aluminum nitride (AlN), silicon carbide (SiC), silicon, or a plastic orpolymeric material such as polyimide, polyester etc. In some aspects,such substrates comprises a flexible circuit board, which can allow thesubstrate to take a non-planar or curved shape allowing for providingdirectional light emission with the solid state emitters also beingarranged in a non-planar manner.

In some aspects, LEDs 102 a-c can be horizontally structured so thatLEDs 102 a-c can be electrically connected to traces 108 a-b without theuse of wire bonding. For example, each of LEDs 102 a-c can be ahorizontally structured device where each electrical contact (e.g., theanode and cathode) can be disposed on a bottom surface of the LED 102a-c. Apparatus 100 includes die attach material 130, e.g., solder bumps.Die attaching LEDs 102 a-c using any suitable material and/or technique(e.g., solder attachment, preform attachment, flux or no-flux eutecticattachment, silicone epoxy attachment, metal epoxy attachment, thermalcompression attachment, bump bonding, and/or combinations thereof) candirectly electrically connect LEDs 102 a-c to traces 108 a-b withoutrequiring wire bonds.

In some aspects, each of LEDs 114 a-c can be a device that does notcomprise angled or beveled surfaces. For example, each of LEDs 114 a-ccan be an LED device that comprises coplanar electrical contacts on oneside of the LED (bottom side) with the majority of the light emitting ortransmitting surface being located on the opposite side (upper side),also know as a “flip-chip”. LEDs 114 a-c can be bump bonded to tracesusing bumps of solder (or other appropriate conductive material) andforce, energy (e.g., ultrasonic), and/or heat.

In some aspects, LED devices 110, 140 and 160 can optionally includediffuse layers for optics, lenses, polarizers, anti-reflective (AR)coating, anti glare, micro lenses, light steering, parallax barrier,lenticular arrays, and so on. As a result, the diffuse reflection ofsuch devices can be 5% or less in the visible part of the spectrum.

In some aspects, a method for making a wavelength conversion component,comprises: providing a transparent substrate having an upper surface anda lower surface; applying a phosphor compound to the upper surfaceand/or lower surface of the transparent substrate; and curing thetransparent substrate with applied phosphor compound, wherein thewavelength conversion component is configured to alter a wavelength of alight emitted from a light source when positioned proximate to the lightsource. The transparent substrate can comprise a sapphire wafer, and thephosphor compound can comprise a mixture of phosphor and silicone. Themixture of phosphor and silicone can comprise a ratio of about 1:1 toabout 5:1. Applying a phosphor compound to the upper surface and/orlower surface of the transparent substrate results in a substantiallyuniformly applied phosphor compound to the transparent substrate suchthat the phosphor compound is conformal to the transparent substrate. Alaser can be used to cause an internal damage layer in the transparentsubstrate. The method can comprise singulating the transparent substrateafter application of the phosphor compound to provide a wavelengthconversion component of a desired size, and the singulation can comprisesingulating the transparent substrate prior to application of thephosphor compound to provide a wavelength conversion component of adesired size. Applying a phosphor compound to the upper surface and/orlower surface of the transparent substrate can comprise spraying, screenprinting and/or dispensing. A silicone compound on the phosphor compoundcan be applied to the upper surface and/or lower surface of thetransparent substrate.

A method in some aspects can comprise: providing a submount comprisingan upper surface and a bottom surface; attaching one or more lightemitters on the upper surface of the submount, the one or more lightemitters comprising an upper surface, a lower surface, and one or moresides; applying a light affecting material to the upper surface of thesubmount and adjacent to the one or more sides of the one or more lightemitters; and applying a wavelength conversion component on the uppersurface of the one or more light emitters. The light affecting materialcan comprise a reflective material. The light affecting material cancomprise TiO₂. The light affecting material can surround the sides ofthe one or more light emitters disposed on the upper surface of thesubmount. Applying a light affecting material can further compriseapplying a dam material on the upper surface of the submount prior toapplying the light affecting material, wherein the dam material isconfigured to contain the light affecting material on the upper surfaceof the submount and adjacent to the one or more sides of the one or morelight emitters after application of the light affecting material,whereby the one or more light emitters are surrounded by the lightaffecting material. The dam material can be applied on the upper surfaceof the submount to a height substantially similar to a height of the oneor more sides of the one or more light emitters, wherein the dammaterial is configured to contain enough light affecting material tosurround the one or more light emitters at a depth substantially similarto the height of the one or more sides of the one or more lightemitters. The wavelength conversion component can comprise a transparentsubstrate comprising an upper and lower surface, and a phosphor compounddisposed on at least one or both of the upper and/or lower surface. Thetransparent substrate can comprise a sapphire wafer. The phosphorcompound can comprise a mixture of phosphor and silicone. The wavelengthconversion component can be applied to the upper surface of the one ormore light emitters with the phosphor compound facing down and adjacentto the upper surface of the one or more light emitters. Applying awavelength conversion component on the upper surface of the one or morelight emitters further can comprise adding a silicone layer to the uppersurface of the one or more light emitters prior to applying thewavelength conversion component. The silicone layer can further comprisefumed or fused silica. Applying the light affecting material can occurprior to applying the wavelength conversion component. Applying thewavelength conversion component can occur prior to applying the lightaffecting material. A method can further comprise making the wavelengthconversion component, comprising: providing a sapphire wafer having anupper surface and a lower surface; applying a phosphor compound to theupper surface and/or lower surface of the transparent substrate; andcuring the transparent substrate with applied phosphor compound, whereinthe wavelength conversion component is configured to alter a wavelengthof a light emitted from a light source when positioned proximate to thelight source.

In some aspects, a light emitting diode (LED) component, can comprise: asubstrate for a light emitting diode (LED); one or more copper traces onthe substrate; a gold interface on the one or more copper traces; analuminum pad configured for electrically connecting with the LED; and alayer of titanium between the aluminum pad and gold interface, whereinthe layer of titanium is configured to prevent, substantially prevent,or minimize galvanic action between the aluminum pad and gold interface.The layer of titanium can be configured to extend beyond an outerperiphery of the aluminum pad. The substrate can be aluminum nitride.

In some aspects, a method of making a light emitting diode (LED)component comprises: providing a substrate for a LED; providing one ormore copper traces on the substrate; providing a gold interface on theone or more copper traces; applying a first photo mask to create anopening on the gold interface and applying a layer of titanium; andapplying a second photo mask to create an opening on the layer oftitanium and applying an aluminum pad configured for electricallyconnecting with the LED, wherein a layer of titanium is provided betweenthe aluminum pad and gold interface, wherein the layer of titanium isconfigured to prevent, substantially prevent, or minimize galvanicaction between the aluminum pad and gold interface. The layer oftitanium can be configured to extend beyond an outer periphery of thealuminum pad. The substrate can be aluminum nitride.

While the subject matter has been has been described herein in referenceto specific aspects, features, and illustrative embodiments, it will beappreciated that the utility of the subject matter is not thus limited,but rather extends to and encompasses numerous other variations,modifications and alternative embodiments, as will suggest themselves tothose of ordinary skill in the field of the present subject matter,based on the disclosure herein.

Aspects disclosed herein can, for example and without limitation,provide one or more of the following beneficial technical effects:reduced cost of providing solid state lighting apparatuses; reducedsize, volume, or footprint of solid state lighting apparatuses; improvedefficiency; improved color rendering; improved thermal management;simplified circuitry; improved contrast, improved viewing angle;improved color mixing; improved reliability; and/or simplified DC or ACoperability.

Various combinations and sub-combinations of the structures and featuresdescribed herein are contemplated and will be apparent to a skilledperson having knowledge of this disclosure. Any of the various featuresand elements as disclosed herein can be combined with one or more otherdisclosed features and elements unless indicated to the contrary herein.Correspondingly, the subject matter as hereinafter claimed is intendedto be broadly construed and interpreted, as including all suchvariations, modifications and alternative embodiments, within its scopeand including equivalents of the claims.

What is claimed is:
 1. A light emitter device comprising: a submountcomprising an upper surface and a bottom surface; one or more lightemitters disposed on the upper surface of the submount, the one or morelight emitters comprising an upper surface and one or more sides; alight affecting material disposed on the upper surface of the submountand adjacent to the one or more sides of the one or more light emitters;and a wavelength conversion component disposed on the upper surface ofthe one or more light emitters.
 2. The device of claim 1, wherein thewavelength conversion component comprises a transparent substratecomprising an upper and lower surface, and a phosphor compound disposedon at least one or both of the upper and/or lower surface.
 3. The deviceof claim 2, wherein the transparent substrate comprises a sapphirewafer.
 4. The device of claim 2, wherein the phosphor compound comprisesa mixture of phosphor and silicone.
 5. The device of claim 2, whereinthe phosphor compound is substantially uniformly applied to thetransparent substrate and/or is conformal to the transparent substrate.6. The device of claim 1, wherein uniformity of color produced by thedevice is enhanced.
 7. The device of claim 1, further comprising a clearlayer between the wavelength conversion component and the upper surfaceof the one or more light emitters.
 8. The device of claim 7, wherein theclear layer comprises a silicone and/or an adhesive, and optionallycomprises a scatter compound.
 9. The device of claim 8, wherein thescatter compound comprises fumed silica, fused silica, and/or TiO₂. 10.The device of claim 1, wherein the light affecting material comprises areflective material.
 11. The device of claim 1, wherein the lightaffecting material comprises TiO₂.
 12. The device of claim 1, furthercomprising one or more electrically conductive contacts disposed on thebottom surface of the submount.
 13. The device of claim 1, furthercomprising at least one light emitter electrically connected to one ormore traces on the submount.
 14. A wavelength conversion component,comprising: a transparent substrate having an upper surface and a lowersurface; and a phosphor compound disposed on the upper surface and/orlower surface, wherein the wavelength conversion component is configuredto alter a wavelength of a light emitted from a light source whenpositioned proximate to the light source.
 15. The component of claim 14,wherein the transparent substrate comprises a sapphire wafer.
 16. Thecomponent of claim 14, wherein the phosphor compound comprises a mixtureof phosphor and silicone.
 17. The component of claim 14, wherein thephosphor compound is substantially uniformly applied to the transparentsubstrate and/or is conformal to the transparent substrate.
 18. A lightemitter device comprising: a submount comprising an upper surface and abottom surface; one or more light emitters disposed on the upper surfaceof the submount, the one or more light emitters comprising an uppersurface, and one or more sides; a light affecting material disposed onthe upper surface of the submount and adjacent to the one or more sidesof the one or more light emitters; a wavelength conversion componentdisposed on the upper surface of the one or more light emitters; and alens disposed over and/or affixed to the upper surface of the submountand extending above the one or more light emitters.
 19. The device ofclaim 18, wherein the wavelength conversion component comprises atransparent substrate comprising an upper and lower surface, and aphosphor compound disposed on at least one or both of the upper and/orlower surface.
 20. The device of claim 19, wherein the phosphor compoundcomprises a mixture of phosphor and silicone.